1. Field of the Invention
The present invention relates to an image forming apparatus with a reduction layout function that reduces and arranges document images of multiple pages into one page to print the page on a sheet. Particularly, the present invention relates to an image forming technique about documents containing code symbols, such as bar codes and QR Codes (registered trademark).
2. Description of the Related Art
There is a conventional image forming apparatus that prints code symbols, such as bar codes and QR codes (registered trademark), on a sheet together with characters or images as a marking method for prohibiting copying in a purpose of merchandise management and leakage prevention of personal information or confidential information, etc. On the other hand, there is an image forming apparatus with a reduction layout function that reduces and arranges document images of multiple consecutive pages into one page to print the page on a sheet.
When a code symbol is printed on a sheet, reduction of a layout using the reduction layout function may disable from reading information from the code symbol. Accordingly, when multiple-page documents containing code symbols are reduced and laid out, a code area required to arrange the code symbols of a predetermined size more than the minimum readable size is reserved. Then, the code symbols of the predetermined size are arranged in the code area, and the document images are reduced and arranged in an imaging area formed by removing the code area from an image formable area (see Japanese Laid-Open Patent Publication (Kokai) No. 2006-259045 (JP 2006-259045A)). The reduction layout method disclosed in this publication will be described using FIG. 17.
As shown in FIG. 17, code symbols 902-1 and 902-2 are printed on documents 901-1 and 901-2, respectively. When the two documents 901-1 and 901-2 are reduced as-is so as to be printed in the reduction layout (two-up printing), the code symbols 902-1 and 902-2 may become smaller than the minimum readable size. Accordingly, the code area 904 required to arrange the two code symbols 902-1 and 902-2 of the predetermined size is reserved in the image formable area of the sheet 903. Then, the code symbols 902-1 and 902-2 are converted into conversion code symbols 905-1 and 905-2 of the predetermined size, and the conversion code symbols are arranged in the code area 904.
Moreover, the images of the documents 901-1 and 901-2 are reduced to the document images 907-1 and 907-2, which are arranged in the imaging area 906 formed by removing the code area 904 from the image formable area of the sheet 903 in the reduction layout. Then, the conversion code symbols 905-1 and 905-2 of the predetermined size, and the document images 907-1 and 907-2 are formed as a reduction layout image. This enables to read the code symbols even in the reduction layout.
However, the above-mentioned method needs to reserve the code area in which the code symbols of the predetermined size can be arranged. Accordingly, when four documents are reduced and laid out in one page (four-up layout), or when eight documents are reduced and laid out in one page (eight-up layout), the imaging area that is formed by removing the code area from the image formable area becomes extremely small. As a result, the size of the document image of a desired reduction layout differs from the size of an actual document image significantly.